Compressor.



No. 7|l,689.'

I F. WI'ITl-INNIEIER.4v

GUMPRESSUB.

(Application filed Feb. 15, 1902.)v (no Model.) Y i i I 2 sham-shut 4.

UNITED STATES PATENT OEEICE."`

.SCHELL BROTHERS ICE MACHINE A CORPORATION OF ILLINOIS.

COMPANY, ror CHICAGO, ILLINOIS,

COMPRESSOR.

SPECIFICATION forming part of Letters lPatent N0. 711,689, dated October 21, 1902- Applioationflled February 15| 1902. Serial No; 94.283, (No model To all whom t may concern:

Beit known that I, FREDERICK WITTEN- MEIER, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a new and useful Improvement in Compressors, of which the fol'- lowing is 'a specification.

My invention relates more especially to improved and automatically-operating means for loading the compressor-piston or starting the operation of compression when the supp ly generated by the compressor falls below a certain predetermined limit and for unloading the compressor-piston or stopping the operation of compression when said limit is exceeded.- v

My object is to provide' improved and 'quickly-acting mechanism 4movable under variations in pressure of the compressed fluid for A'automatically loading and unloading the compressor-piston Without interfering with the reciprocation thereof.

In carrying out my invention I provide a suitably-disposed Valved opening or by-pass and operating mechanism'for tlievalve actuated to open it whenever the compressed fluid exceeds a predetermined pressure and close it Whenever the pressure falls below said limit.

In the drawings, Figure l is aA broken side elevation of so much of a double-acting compressor as is necessary to illustratemyimprovements and their operation; Fig. 2, a.

. section taken on line 2 in Fig. l; and Figs. 3

and 4, enlarged broken sections taken, .re-u

1spe'ctively, onV lines 3 and et in4 Fig. 2 Viewed in the direction of the arrows.

A is the cylinder of a double-acting compressor, which may be constructed with .al

Water-jacket a. In the cylinder-heads B,`at each end of the cylinder, are valved inlet or suction ports/b c. The ports l) c communicate through a cored passage with a suctionchamber b', which receives the air or gas to be compressed from an inlet-pipe b2. The discharge-valves at the valve-caps lr, are not shown in detail, butthey communicate with a compression chamber. c', having a discharge-pipe c2. The induction and eduction valves may be of any suitable construction, and the chambers b c communicate with thc respective ports at opposite ends of the cylinder.' In the cylinder is the usual piston upon a pistou-rod C, and the piston reciprocatcs between the opposite cy1inder-heads without material clearance.

In each cylinder-head B, preferably in the position shown, is a cylindrical chamber D, closed at its outer end bya suitable cap d. Adjacent to the inner surface of the cylinder-head the chamber D is provided with a 6o wall or diaphragm D', having a series of openings or ports d', which may be four in number, as shown, and equidistant apart. The chamber D in each cylinder-head communicates through a cored passage D2 with'the 65' adjacent cored suction-passage. The cha-mbers D and passages .D2 form supplemental openingsor by-passes through the cylinder ends. At the inner side ot the )Vall D is a round shallow' recess d2, and the wall is pro- 7o vided with a central opening d". Extending through the cap d and center of the chamber D is a rotary valve-stein E, provided with an enlarged or shouldered part c, fitting through the, opening d?- inthe recess cl2, is va disk valve E', which moves uponfthe inner surface of the wall D. Rigidly .secured to the stem E and sliding against the outer surface of the wall D is a rotary disk valve E?. The valves E E2 have v8o correspoudingop'enings e', which in one movemefnt'of the valve-stem' vE register with the openings d in the wall.

'On the discharge-pipe c2 is a bracket F, sef cuied in place by means of the collars F'.

bracket F is a cylinder-'or chamber F2, open at its'upper end and provided at its lower end with a coupling F3, which communicates,

thi'ough a pipe F4,`witl1 the interior of the dis- 9.o

charge-pipe c2. Between the couplipg F3 and thechamber F2 is a gasketf, forming a valveseat. Extending through the wall of the cylinder F2 is a portf, communicating with a coupling G, snrmounted by a cylinder G', 95

which is open at its fupper end. Between the coupling G and cylinder G' is a gasket g, forming a cushion. Y Y

Iny the cylinder Fzaud fitting upon the seat f is a pistomvalve F5'on a vertical stein F, roo

Integral with this stem E,

Invreg'ral with or suitablysupported by the heads with an arm I.

sliding through a guide F7 on an arm F8 of the bracket F.l On the upper end of the stem F6 is a weight F11.

In the cylinder G', seating upon the cushion g, is ainovable diaphragm or piston-valve G2 on a vertical stem G2. On the upper end of the stem G3 is a slotted coupling G4, and on the upper side thereof is a stem extension G5, movable Athrough a guide F in an arm F10 of the bracket F.

Fulcrumed at its end upon the bracket Fis a lever H, passing through the slot of the coupling G4.

Mounted in bearings 71. on the side of the compressor-cylinder A is a horizontal rockshaft I, provided beyond each of the cylinder- Ou each stem E, just beyond the respectivecap d, is an arm E2, pivotally connected at its free end with the adjacent arm I. At the center of the rock-4 shaft I is an arm 12, and pivotally fastened at its opposite ends, respectively, to the lever H and arm I2 is a rod H.

Presuming, for example, that the area of the opening at the seatfis vone-quarter of a square inch and that itis desired to maintain a pressure on the discharge side of the compressor equal to one hundred pounds to the square inch, a weight F11 of twenty five pounds would be provided. Normally the valves E' E2 are `in a position wherein they close the ports d of the by-passes through D D2. When these valves are closed, the piston upon the stem in its reciprocation will draw fluid through the ports bcand discharge the same as it is compressed to the dischargepipe c2. When the pressure in the dischargepipe exceeds the predetermined limit of,'say, one hundred pounds, it exerts Va pressure against the valve F5 exceeding the resistance of the weight F11, whereby the latter, with the stem F6 and the valve, is raised'in "the cylinder F2 until the valve uncovers the portf. This causes a sudden rush of the compressed fiuid through the pipe F4., coupling F3, and portf to the coupling G, against the under side of the piston G2, sufficient to raise-the latter, its stem, and coupling G4 to swing the lever H upward on its fulcru'm and through the connection H l-2 rock the .shaft I. This rockin g of the shaft causes it through the connections I E2 to turn the valve-stems A?" at each end of the cylinder A and rotate4 the valves AE E2 until the ports e thereon register with and open the ports d' of the bypasses. Immediately that the by-passes are lopened the iiuid discharged by the piston will 'pass through the by-passes to the suctionwh'at below the predetermined limit-say one hundred pounds-the weight F11 overcomes the resistance of the pressure against the lower end of the valve F5 and drops, closing said valve. This relieves the pressure against the under side of the valve G2, permitting it and its stem and the lever H to descend and rock the shaft I to close the by-pass valves E E2, when the compressor-piston will be im- Amediately loaded in the sense of its discharging through the eduction-valves against the back pressure in the pipe o2 and resume work. When the piston F5 falls to its seatj', it uncovers or partly uncovers the portf', wherebythe pressure previously held by the coupling G quickly escapes.

It will be noticed that the area of the lower surface of the valve exposed to pressure from thedischarge-pipec2 increases instantly -that it leaves its seat, so that as soon as the fluid-pressure rises above the point a't which it will startthe valve F5 upward an increased area is exposed to said pressure, causing the valve to be elevated very quickly. The inrush of iiuid against the under side of the valve G2 acts very quickly to raise the latter and close the by-pass valves. These features of my construction are important, because the piston F5 has no mechanism to operate which might, by sticking, interfere With its free movement, and the valve G2 is relieved from the linfiuelnce of the duid-pressure at all times during the Working of the compressor-piston and produces a sudden quick opening and closing of the by-passes under the desired conditions. i

If desired, a spring may be substituted for the weighton the stem F6 and the mechan- IOO ism otherwise variously modified Without dei end, a valve at said opening and means for opening said valvecomprsing a chamber G', a passage extending from the compression side of the compressor to said'chamber, a movable diaphragm in said 'chamber operatively connected with said supplementalopening valve, a Weighted passage opening and closing valve F5, and lever mechanism connected with said diaphragm and supplemental-opening valve, all constructed to operate substantially as set forth.

FREDERICK WITTENMEIER.

In presence of V ALBERT D. BACCI, L. HEISLAR. 

